I was a KDE 2 and 3 user. Then, when the 4 craziness started, I waited until 4.5, something like that. But the "everything is a widget" idea is really weird. With the plus of several bugs, kdm bugs, app launcher bugs, systray bugs, sound mixer eating memory, and, at every minor upgrade, I had to clean up my configurations to get the new version working. If not enough, they announced KDE 5, and all started again.
I never liked Gnome shell. Not to mention all the removing-features-coolaid since 3.
So, I started to use Unity, from Canonical. Smart defaults: launcher at left; when you click in a launcher icon last used window is selected (click again to see all app instances); HUD; the simple notifications; very stable and polished; getting faster every new iteration without major drawbacks (16.04 is really awesome).
Now I can understand why Canonical sometimes follow their own way. They really provide polished and professional UX. Sometimes I disagree with some decisions (I really wish they keep working with Wayland), but in general, I really enjoy their products.
"Oh what wouldn't I give to be spat at in the face..." -- a prisoner in "Life of Brian"